On March 25, the MESSENGER spacecraft completed its 4,000th orbit of Mercury, and the lowest point in its orbit continues to move closer to the planet than ever before. The orbital phase of the MESSENGER mission, which was ...

Researchers from Brown University have completed a new analysis of an ancient Martian lake system in Jezero Crater, near the planet's equator. The study finds that the onslaught of water that filled the crater was one of ...

One of the four Cluster satellites has shifted its orbit to ensure a safe reentry when the time comes, as well as providing a rare opportunity to study how a satellite's exhaust plume interacts with the solar wind.

Researchers at the University of Rochester and their collaborators have developed a way to transfer 2.05 bits per photon by using "twisted light." This remarkable achievement is possible because the researchers used the orbital ...

MESSENGER will not go gentle into that good night. The mission will end sometime this spring, when the spacecraft runs out of propellant and the force of solar gravity causes it to impact the surface of Mercury. But the team ...

(Phys.org)—A trio of researchers affiliated with Delft University in The Netherlands, has come up with a new way to provide propulsion for CubSats—use frozen water as fuel. In their paper published in Acta Astronautica, ...

Orbit

In physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star.

Historically, the apparent motion of the planets were first understood in terms of epicycles, which are the sums of numerous circular motions. This predicted the path of the planets quite well, until Johannes Kepler was able to show that the motion of the planets were in fact elliptical motions.[citation needed] Isaac Newton was able to prove that this was equivalent to an inverse square, instantaneously propagating force he called gravitation.[citation needed] Albert Einstein later was able to show that gravity is due to curvature of space-time, and that orbits lie upon geodesics. This is the current understanding.